/**********
This library is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)

This library is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
more details.

You should have received a copy of the GNU Lesser General Public License
along with this library; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
**********/
// "liveMedia"
// Copyright (c) 1996-2018 Live Networks, Inc.  All rights reserved.// A filter that converts a MPEG Transport Stream file - with corresponding index file
// - to a corresponding Video Elementary Stream.  It also uses a "scale" parameter
// to implement 'trick mode' (fast forward or reverse play, using I-frames) on
// the video stream.
// C++ header

#ifndef _MPEG2_TRANSPORT_STREAM_TRICK_MODE_FILTER_HH
#define _MPEG2_TRANSPORT_STREAM_TRICK_MODE_FILTER_HH

#ifndef _FRAMED_FILTER_HH

#include "FramedFilter.hh"

#endif

#ifndef _MPEG2_TRANSPORT_STREAM_INDEX_FILE_HH

#include "MPEG2TransportStreamIndexFile.hh"

#endif

#ifndef TRANSPORT_PACKET_SIZE
#define TRANSPORT_PACKET_SIZE 188
#endif

class MPEG2TransportStreamTrickModeFilter : public FramedFilter {
public:
    static MPEG2TransportStreamTrickModeFilter *
    createNew(UsageEnvironment &env, FramedSource *inputSource,
              MPEG2TransportStreamIndexFile *indexFile, int scale);

    Boolean seekTo(unsigned long tsPacketNumber, unsigned long indexRecordNumber);

    unsigned long nextIndexRecordNum() const { return fNextIndexRecordNum; }

    void forgetInputSource() { fInputSource = NULL; }
    // this lets us delete this without also deleting the input Transport Stream

protected:
    MPEG2TransportStreamTrickModeFilter(UsageEnvironment &env, FramedSource *inputSource,
                                        MPEG2TransportStreamIndexFile *indexFile, int scale);

    // called only by createNew()
    virtual ~MPEG2TransportStreamTrickModeFilter();

private:
    // Redefined virtual functions:
    virtual void doGetNextFrame();

    virtual void doStopGettingFrames();

private:
    void attemptDeliveryToClient();

    void seekToTransportPacket(unsigned long tsPacketNum);

    void readTransportPacket(unsigned long tsPacketNum); // asynchronously

    static void afterGettingFrame(void *clientData, unsigned frameSize,
                                  unsigned numTruncatedBytes,
                                  struct timeval presentationTime,
                                  unsigned durationInMicroseconds);

    void afterGettingFrame1(unsigned frameSize);

    static void onSourceClosure(void *clientData);

    void onSourceClosure1();

private:
    Boolean fHaveStarted;
    MPEG2TransportStreamIndexFile *fIndexFile;
    int fScale; // absolute value
    int fDirection; // 1 => forward; -1 => reverse
    enum {
        SKIPPING_FRAME,
        DELIVERING_SAVED_FRAME,
        SAVING_AND_DELIVERING_FRAME
    } fState;
    unsigned fFrameCount;
    unsigned long fNextIndexRecordNum; // next to be read from the index file
    unsigned long fNextTSPacketNum; // next to be read from the transport stream file
    unsigned char fInputBuffer[TRANSPORT_PACKET_SIZE];
    unsigned long fCurrentTSPacketNum; // corresponding to data currently in the buffer
    unsigned long fDesiredTSPacketNum;
    u_int8_t fDesiredDataOffset, fDesiredDataSize;
    float fDesiredDataPCR, fFirstPCR;
    unsigned long fSavedFrameIndexRecordStart;
    unsigned long fSavedSequentialIndexRecordNum;
    Boolean fUseSavedFrameNextTime;
};

#endif
